Such an electronics card may form part of a motor vehicle tachometer with a pointer display, or the like. The electronics card comprises a printed circuit board with electrical tracks and carrying firstly electronic components that are electrically connected to one another by said electrical tracks to which they are soldered, and secondly a piece of equipment such as a stepper motor that is powered and controlled by the printed circuit while also being carried thereby.
Specifically, the printed circuit together with its electronic components serve to process the signal needed for powering the stepper motor that carries the pointer of the tachometer, so as to place said pointer continuously in an angular position that is representative of the actual speed of the vehicle.
When fabricating such an electronics card, the electronic components are soldered to the tracks of the printed circuit board using a so-called reflow method. Under such circumstances, the solder is initially placed on the printed circuit board at the soldering locations prior to placing the electronic components on the board. The assembly is then inserted into an oven, thereby causing the terminals of each of the electronic components to be soldered to the tracks of the printed circuit.
Since a piece of equipment such as a motor includes portions made of plastics material that cannot withstand the temperatures of a reflow oven, such a motor is fastened in a separate operation.
Under such circumstances, the motor is placed on the printed circuit board by engaging its pins in holes that pass through the board, and then the pins are subsequently soldered to connect them electrically to the tracks of the printed circuit board, while also rigidly securing the motor to the board.
This operation of soldering the pins of the motor is generally performed by a soldering operation known as “wave (or flow)” soldering, during which molten solder is brought into contact with each pin for soldering so as to solder it to the corresponding track.